Carton



J. c. BENSC'HOTER Sept. 4, 1956 CARTON '2 Sheets-Shut 1 Filed July 20, 1953 INVENTOR. JAMES C BENSGHOTEI? 4 r TORNEY P 3 1956 I J. c. BENSCHOTER CARTON Filed July 20, 1953 2 Sheets-Sheet 2 H mm TO M V M E B C Q M w ATTORNEY P atented Sept. 4, 1956 CARTON James C. Benschoter, Stockton, Califi, assiguor to FibreboardProtlucts Inc., San Francisco, Caliti, a corporation of Delaware Application July 20, 1953, Serial No. 368,917 2 Claims. Cl. 229-37 This invention relates to new and useful improvements in cartons for materials which are poured into containers in molten state and subsequently solidify. Thus, the present invention finds a most useful application in paperboard cartons for asphalt.

As illustrated in the accompanying drawings, and subsequently described herein, a carton which is hexagonal in cross-sectionmay be employed It will be understood, however, that the carton may be of any polygonal shape.

Conventional cartons of paperboard and other suitable materials are generally formed from a substantially rectangular blank which is divided by longitudinal crease lines into a plurality of body panels corresponding in number to the number of sides of the carton. On one side of the blank a short stitching flap is formed; the function of this stitching flap is to join the two longitudinal edges of the blank into a carton body. The stitching fiap may be attached to the cooperating longitudinal edge of the blank by various means, including glue and adhesive tape; as hereinafter described and as illustrated in the accompanying drawings, metallic staples are employed, it being understood that other attaching means may be used. One of the characteristics important to the present invention is the fact that the stitching flap is positioned on the outside, rather than the inside, of thecarton in assembled condition.

To close the top and bottom of the assembled carton, the blank is fabricated with a plurality of end closing flaps along its top and its bottom edges, the number of top flaps and of bottom flaps corresponding to the numher of sides of the carton. The end flaps at the top are separated from the body panels by a common transverse crease line, and the bottom end flaps are separated from the body panels by another common transverse crease line. The individual flaps are separated from adjacent flaps by cuts extending from the ends of the blank toward the transverse crease lines and being positioned in alignment with the longitudinal crease lines.

One of the problems encountered in packaging molten materials such as asphalt, has been the tendency of such materials to leak at the corner where the cuts meet the body panels. This problem has been overcome partially by making the cuts which separate the end flaps terminate a short distance of about one-half inch from the transverse crease line. When the flaps are folded into position in the elected carton the material between the terminus of the cuts and the crease line is folded under in a dart tuck which prevents leakage at the corner.

However, prior to the present invention, no satisfactory means has been found to prevent leakage of the moltemmaterial at the bottom corner where the two side edges of the blank meet along the stitching flap because no material was provided to tuck under at this corner. The present invention solves this problem by extending the stitching flap, preferably a short distance below the bottom transverse crease line which defines the bottom end flaps, and then fastening the extension of the stitching flap to the adjacent end flap in the set-up carton but on a panel at the opposite side of the blank. A short cut is formed between the extension of the stitching flap :and the adjacent end flap on the panel to which the stitching fiap is secured, this cutterminating from the bottom transverse crease line the same distance that the other cuts which define the end flaps terminate. Thus, the uncut material adjacent the end of the cut which defines the extension of the stitching flap is tucked when the carton is erected and prevents leakage at this corner.

Another feature and advantage of the invention resides in the fact that the stitching flap and its extension are on the outside of the carton. Hence, when th carton is erected the extension of the stitching flap is stretched as it is folded around the corner between the bottom of the carton and the sides, and the stretching of the extension exerts force on the tuck at the corner to close the corner tightly to cooperate in preventing leakage.

In the drawings:

Fig. 1 is a plan of the blank employed to erect the instant carton.

Fig. 2 is a perspective of the assembled carton viewed from above.

Fig. 3 is a perspective of the carton viewed from below.

Fig. 4 is a top plan of the assembled carton.

Fig. 5 is a bottom plan thereof.

Fig. 6 is an enlarged fragmentary view of the carton after the stitching flap and the end extension thereof have been fastened to the cooperating meeting body panel and end flap but before the end flaps have been folded inward to form the bottom of the carton.

Fig. 7 is a fragmentary transverse section taken substantially along the line '77 of Fig. 6.

Fig. 8 is a fragmentary section taken substantially along the line 8+8 of Fig. 5.

The blank for the carton which is the subject of this invention is a flat, substantially rectangular piece of corrugated paperboard or similar suitable material. A socalled hexagonal carton is preferred for the packaging of asphalt; and the blank is divided into six rectangular body panels 11 by fivelongitudinal crease lines 12, a transverse top crease line 13 spaced downward from the top of the blank and a transverse bottom crease line 14 spaced upward from the bottom of the blank. Along one outside edge of the blank is a stitching flap 16 of a width substantially less than the width of the body panels 11 and separated from the adjacent body panel by a longitudinal crease line 17. The top edge of said stitching flap 16' terminates substantially in alignment with the top transverse crease line 13, but the bottom edge of the stitching flap extends for a short distance of approximately one inch below the bottom transverse crease line 14in What is termed herein the end extension 18 of the stitching flap.

The material above and below the top and bottom transverse crease lines comprise the top and bottom end flaps 21 and 22, respectively, and for such purpose cuts 23 are formed in line with the longitudinal crease lines 12, said cuts extending inward from the top and bottom edges of the blank but terminating before reaching the top and bottom transverse crease lines a distance of about one-half inch, thereby providing material indicated by reference numeral 24 which, when the end flaps 21 and 22 are folded inward as the carton is erected, tuck under the flaps in a dart tuck which prevents leakage at the corners. Each body or side panel 11 is approximately 21 inches long and 7 inches wide, and each cut flap is approximately 6 by 7 inches; the stitching flap extension 13 being preferably about 1 inch long, and about 1 /2 inches wide.

In accordance with the present invention, a short cut 26 is formed in line with longitudinal crease line 17, said out extending up from the bottom edge of end extension 18 and terminating below transverse crease line 14 leaving uncut material 27 between the end of cut 26 and crease line 14. This uncut material 27 performs a very important function in that when the carton is erected and the bottom flaps 22 are folded inward, the material 27 is folded inside in a dart tuck which seals the corner 29 where the material is located.

After the blank has been fabricated, the first assembly step, which is ordinarily performed at the carton factory, is to join the longitudinal edges of the blank by stitching flap 16. In accordance with the present invention, the sitching flap 16 is placed on top of the outside marginal edge of the body panel 11a on the opposite side of the blank. To secure the stitching flap to the body panel 11a, metallic staples 31 are employed in the carton illustrated herein, it being understood that other means may be employed. Such staples 31 are spaced along the length of the stitching flap 16. One important feature of the invention is the fact that end extension 18 is fastened to end flap 22a, and for such purpose at least one staple 31a is employed. (See Fig. 6.)

Customarily, the cartons are shipped from the carton factory to the place where they are to be filled in collapsed condition, i. e. with the stitching flap 16 joined to the opposite body panel 11a and end extension 18 joined to the flap 22a, but otherwise flat.

When the carton is about to be filled, a workman spreads the collapsed carton into sh'ape-in this case a hexagonal prismand then folds the bottom end flaps 22 inwardly to form the bottom of the carton. In folding the end flaps 22, they are interlocked, as illustrated herein, by interposing the right edge of each end flap under the left edge of the adjacent flap so that each flap holds down a portion of one adjacent flap and is, in turn, held down by the other adjacent flap. It should be noted that the end flaps are so folded that, as best shown in Figs. 3 and 5, the end extension 18 is on the outside.

During the course of the folding operation just described the material indioated by reference numeral 24 is folded under the flap 22 which overlies it in a dart tuck and this material tends to prevent leakage at the corners. The material 27 at the extension 18 is likewise folded under in a dart tuck and this tends to seal against leakage the one corner 29 which would otherwise have no such protection.

As shown in Fig. 8, since end extension 18 is fastened to end flap 22a, when the end flaps 22 are folded inward considerable tension is imparted to end extension 18 as it is folded around the corner 29 since, being on the outside, it must extend over a greater distance for its original length than the underlying end flap 22a. This tension imparts a force against the corner 29 which compresses the dart tuck formed from material 27, and further helps to seal the corner against leakage.

In setting up the cartons, heads or liners are employed. Such liners are of paperboard, and are cut in the shape of the cross-section of the interior of the carton, i. e. hexagonal in the case of the carton illustrated. The liner also helps prevent leakage at the corners.

After the bottom has been formed and the bottom liner 36 inserted at the bottom of the carton, molten asphalt 38 is poured into the carton to near the top. A top liner 37 similar to bottom liner 36 may be employed on top of the asphalt. Thereafter, the top end flaps 21 are folded inward in a pattern similar to that of the bottom end flaps (see Figs. 2 and 4). Leakage at the top of the carton is ordinarily not a problem but an extension on the stitching flap may be also employed at the top, if so desired. Also, although the extension is relatively short, being just long enough to apply the previously described force to seal the cover at the stitching flap, it can be made longer if so desired.

The carton thus described will not leak during the period of time while the asphalt is solidifying by reason of the described construction. The prevention of leakage solves one of the most important problems in the employment of fiber containers for products which are filled in molten condition.

I claim:

1. A carton adapted to hold solidified material poured into the carton in molten state, comprising a single blank of paperboard having more than four rectangular body panels hingedly connected along spaced parallel longitudinal crease lines; a transverse crease line and a cut substantially in line with each of said longitudinal crease lines dividing said blank into a plurality of substantially rectangular closure flaps corresponding in number to the number of body panels, each of said cuts terminating short of such transverse crease line to provide at the corners of juncture of each of said closure flaps with each of said body panels uncut material between the inner end of each cut and the transverse crease line; said blank being folded along said longitudinal crease lines to form such carton with a cross sectional shape having more than four sides; a stitching flap connected to a first of said body panels forming an outermost panel of the blank and overlapping the outside marginal portion of a second of said body panels forming the other outermost panel of the blank; means securing said stitching flap to said second body panel; an end extension on said stitching flap adjacent said transverse crease line, said end extension being separated from the closure flap connected to said first body panel by an inwardly extending cut terminating short of said transverse crease line, the material of said blank adjacent said end extension and between the inner end of said latter cut and said transverse crease line being uncut; and means securing said extension to the outside of the closure flap connected to said second body panel; said closure flaps being folded inwardly in successive overlapping relationship whereby the uncut material at each of said corners of juncture is compressed and forms a seal at each of said corners, each closure flap having its inner end edge terminating at the longitudinal axis of the carton and said closure flap connected to said second body panel overlying the closure flap connected to said first body panel whereby said extension is placed under tension and said uncut material adjacent said end extension is also compressed and forms a seal at such extension corner to minimize leakage of the molten material at the extension corner when said molten material is poured into the carton.

2. A carton according to claim 1 in which the paperboard blank is formed from corrugated paperboard.

References Cited in the file of this patent UNITED STATES PATENTS 1,472,211 Gallistel Oct. 30, 1923 2,142,342 Bensel Jan. 3, 1939 2,271,455 Finn Jan. 27, 1942 2,285,174 Simons June 2, 1942 2,439,435 Richardson et al Apr. 13, 1948 2,485,235 Graf Oct. 18, 1949 2,523,488 Williamson Sept. 26, 1950 2,553,803 Zinn May 22, 1951 2,670,127 Gleason et al. Feb. 23, 1954 FOREIGN PATENTS 113,433 Australia July 4, 1941 

